Flash steam-generator.



No. 790,878. 4 PATENTED MAY 23, 1905.

.R. J. MINER. FLASH STEAM GENERATOR.

APPLICATION FILED MIA-BN2 1905.

2 SHEETS8HEET 1.

No. 790.378. Y PATENTED MAY 23, 1905.

, R. J.,MINBR.

FLASH STEAM GENERATOR.

APPLICATION FILED MAR. 2, 1905.

2 B HEETS8HIIET 2.

Fig. 4.

UNITED STATES l 'atented May 23, 1905.

PATENT OFFICE.

ROBERT J. MINER, OF GREENWICH, CONNECTICUT, ASSIGNOR OF ONE- HALF TO WINTHROP WAITE, OF EAST ORANGE, NEW JERSEY.

FLASH STEAM-GENERATOR.

SPECIFICATION forming part of Letters Patent No. 790,378, dated May 23,1905. Application filed March 2, 1905. Serial No. 248,165.

To (ZZZ whom, it may concern: I

Be it known that 1, ROBERT J. MINER, of the town of Greenwich, county ofFairfield, and State of Connecticut, have invented certain new anduseful Improvements in Flash Steam-Generators, fully described andrepresented in thefollowing specificationand the accompanying drawings,forming a part of the same.

This invention relates particularly to that class of steam-generatorsknown as of the flash type, in which steam is produced by the constantapplication of heat to water rapidly circulating under pump -pressurewithin a coil of tubes so arranged over the fire that at no point in thecoils is the heat not directly ap lied.

The object 0 this invention is to provide a simple means of flash steamgeneration for automobiles, steam-launches, house-heating, &c., which,while producing steam of very high pressure or expansion, will notproduce steam of too high a temperature, as it is a well-known fact thatsuperheated steam of too high a temperature seriously interferes withthe proper lubrication of engine-cylinders, &c., causing much seriousdamage thereby.

Still another object of this invention is to secure at all times fromthe generator a delivery of perfectly dry steam without unduesaturation. How this object is attained will be readily seen from thespecification.

A still further object of this invention is to generate steam in theshortest possible length of time from when the cold water enters theenerator to the time it is delivered in the form of superheated steam atthe steam-delivery point thereof, thereby saving fuel and avoiding thenecessity of a somewhat long Wait while first getting up steam, as isthe case with most steam-boilers in existence to- (la till anotherobject of this invention, and a very im ortant one, is to provide meanswhereby the coil wherein the vapor flashes into steam and becomes hotwill not become overheated, thereby avoiding scaling of the metal, whichscale particles are sometimes carried with the steam into the cylindersof the engines, with consequent injury to the latter, and prolonging thelife of that part of the generator, as well as the life of the entiregenerator itself.

These objects are accomplished by the means shown in the annexeddrawings, in which Figure 1 is a front view of the generator inelevation; Fig. 2, a plan view of the top of the generator looking downthrough the same toward the fire; Fig. 3, a view of the feed-watersection of the generator, shown in perspective, while Fig. 4 shows aplan view of one of the coils constituting the main or steam section ofthe generator.

The enerator is made of coils either bent in circular fashion, as isshown in the annexed drawings, or in square or rectangular shaped flatcoils, depending upon the requirements of use, &c. Each coil isfashioned flat, Worm style, of one piece of tubing, as is shown in Fig.4. The coil is so bent as to leave open a small portion of its surface,approximately onethird, this open space being invariably in the centerof the coil, as shown by letter a in Fig. 4, so that when all the coilsare assembled or superimposed one upon another, as shown in Fig. 1,there remains open through the center of the generator a space eithercircular or square or rectangular, according to the shape of the boiler,as is shown in Fig. 2 by theletter a. This space is immediately over thecenter of the'fire and approximates one-third of the entireheatingsurface of the boiler. Through this open space is inserted asecond coil 5, rising from t e bottom fire-coils c c, (which latter willbe described more specifically later on,) wound sion of the lower end ofthe coil 1). (See Fig. 3.) These bottom fire-coils c 0, taken with thespiral riser-coil b, as shown in Fig. 3, constitute what may bedesignated as the feedwater section of the boiler.

The bottom fire-coils c c, referred to in the paragraph above as theflattened-out extension of the riser-coil b, are made flat, Wormwound.From what has been said in reference to this second risercoil b,internally arranged within the larger or main coils d d, Fig. 1, it willbe seen that the bottom coils c c are in immediate proximity to theflame and being built of smaller tubing andv having thicker walls thanthe main orlarge coils d d protect the latter at the bottom of thegenerator from the intense heat of the fire. As the cold water is fedinto the small coils c c at the bottom, just referred to, and is forcedby the action of the supply-pump continuously around them and up thesmall spirally-wound central riser-coil b, connected therewith, it willbe readily seen that they never can become overheated as long as theboiler is in action, which is a radical departure from the effectobtained from the use of those generators whose construction providesfor the introduction of the feed-water into the top of the same,allowing it to flow toward the bottom, flashing into steam somewhere inthe middle, and superheating in the coil next to the fire at the bottom,from whence it is delivered to the engine, &c. In this latter method thebottom coil, containing, as it does, nothing but superheated steam,itself of very high temperature, is subjected to a very severeoverheating, becoming red-hot in normal action, and sometimes burningout or scaling the metal of the tube. In my generator steam is notproduced at any point within this small tube or feed-water section b.The function of this section b is simply to heat up the water to a highdegree, so that by the time it reaches main coil (1, directly overfire-coils c 0, (see Fig. 1,) it is in the form of a saturated vapor.Two obj cots are thus accomplished in this feed-Water section. First, itprotects the steamholding bottom coil d, Fig. 1, from the intense heatby baffling the flame and taking upon itself the brunt of the same, and,second, it renders the production of steam very rapid, as the cold waterbeing continually forced through the small tubes 0 c, Fig. 3 and Fig. 1,immediately over the fire tends to heat very quickly and continuesheating all the way up the spiral coil 6 in the center, as this centeris directly in the highest heat Zone.

Continuing the construction of the main or large coil-sectiondd, Fig. 1,of the generator or boiler after the feed-water or central spirallywoundsection b is connected with the top coil (1, as aforesaid, the maincoils d d, Fig. 1, succeed each other in layers, being simply connectedby their outside ends by means of nipples preferably removed from theheat zone, the end of each upper coil being bent sufficiently downwardto properly make connection with the slightly-upturned end ofthesucceedinglowercoil, as shown in Fig. 4. The coils are connectedeither from their outside ends or their inside ends. If the latter, ofcourse the outside end of the upper coil must be left long enough to runacross to the inside end of the next succeeding lower coil, and viceversa, as the ends may happen to be brought together; but in actualconstruction it is preferable to make allconnections bet-ween coils atthe outside away from the heat zone, which is naturally more intense inthe center. Another reason for my preference in making the coilconnections away from the center is that in case of injury to any onecoil the connection is more easilygotten at, thus facilitating repairs.The coils are not superimposed in absolute regularity one above another,being slightly staggered, so as to present all possible heating-surfaceto the fire. This coil construction as aforesaid continues to a pointanywhere between the top main coil (Z, Fig. 1, and the last or bottommain coil (1, Fig. 1, but more particularly to a point about one-thirdof the way down the main coils (Z (Z of the boiler, which point inactual practice, by way of example, could be the sixth coil from thetop. At this point, to which the circulation of saturated vapor has beenin. downward motion, I carry the end of the coil direct along theoutside of the boiler down to the bottom main or large coil, asdesignated in Fig. 1 by the letter e. The end of this down-drop tube ais connected with and discharges into the bottom main coil d preciselyas the coils preceding above have been connected. This bottom main coild, into which the downdrop tube a discharges, is immediately above thefire-coils c c and is protected by them from the full force of theflame, as hereinbefore stated. From this point on I continue themain-coil construction (1 (Z as formerly, except that I superimpose thecoils with their connections one above the other in such manner that thecirculation of vapor takes on an up motion just the reverse of the downmotion referred to in the first upper coils (I (Z before the droppingdown from the sixth coil to the lowest bottom main coil, as shown by thedownward-leading pipe 0. This up motion continues for the remainingspace left between the bottom main coil (Z and the lowest upper coil(here, by way of example, the sixth) or the coil from whence the downward-leading tube 0 proceeds. In actual practice this upward circulationwould continue to a point anywhere between the top and bottom maincoils, but preferably twothirds the length up the boiler, or, by way ofexample, to a point between the ninth and tenth coil from the bottommain coil (1, supposing the boiler contained in all fifteen coilsexclusive of the smaller-diameter fireopposing feed-water coils c c atthe extreme lower end of the generator, as aforementioned. At thispoint, in example, as above, between the ninth and tenth main coilscounting upward, as aforementioned, I take my live steam for delivery tothe engine, &c., at the point h, as shown in Figs. 1 and 2.

In actual operation cold water is fed under pump-pressure to the bottomsmaller firecoils c c at the point f, as shown in Fig. 3, through whichit circulates immediately'over the flame and from which it rises withinthe spirally-wound central coil 1) of same diameter as the fire-coils tothe top of the generator. form of hot water into the top main or largecoil, as shown in the point gin Fig. 2. It circulates through this maincoil and the succeeding lower main coils d d in downward motion,gettinghotter and hotter each second as it nears the fire. As it passesfrom the last of these upper main coils d d it is suddenly droppedthrough the pipe 0, Fig. 1, to thebottom main coil (1, which issufficiently near to the flame to instantly flash into steam what up tothis point has been an ever-increasingly-heated saturated vapor, butwhich is nevertheless, on account of the protection afforded by thesmall feed-water coils c c, enough removed from the fire to be perfectlyfree from overheating or becoming normally red-hot, even though itcarries only steam within itself. From this bottom main coil cl thesteam is led in an upward motion gradually away from the intense heatzone, drying out and becoming sufliciently hot to prevent condensation,so that when it reaches the delivery-point h, Fig. 1, which isapproximately two-thirds the way up the boiler and At this point it isdelivered in thespecially observed that this enerator can be constructedin other forms t an circular, varying as to conditions of use, &c.,Without changing the construction as hereinbefore described. Thisenables my invention to be adapted to diflerent styles of automobiles,such as large and powerful steam-trucks demanding larger steam capacitythan the cir cular form of boiler might be able to provide.

I claim as my invention In a flash steam-generator consisting of anumber of coils superimposed one above another and connected with eachother, and which have a number of flat fire-coils placed immediatelyabove the flame, said flat firecoils being of less inside and outsidediameter than the upper, outer main coils, the lower of which lattercoils they are designed to protect from the full force of the flame; thecombination of a pipe connected with, and leading the discharge of vapordownward from the upper portion of the coils in the generator, andconnected with and discharging into the bottom coils of the generator,from which latter coils the vapor rises upward to the point of finaldelivery as set forth.

ROBERT J. MINER. [L. s.]

In presence of HENRY W. RowLEY, HENRY R. WAITE.

